Concentrated fabric softening compositions have been extensively described in the art, and one aspect which has often been discussed is the viscosity of these concentrated compositions; indeed these concentrated compositions are typically extremely viscous and the prior art has often described means by which the viscosity of these concentrated compositions could be controlled or decreased. One aspect which has been much less dealt with is the viscosity of these concentrated compositions upon dilution; indeed it has been observed that the viscosity of such concentrated compositions dramatically drops upon dilution, and this viscosity loss is clearly undesirable, essentially in terms of consumer acceptance.
It is therefore an object of the present invention to provide a concentrated fabric softening composition which has an acceptable viscosity in the concentrated form, and which retains acceptable viscosity after it has been diluted.
This technical problem was discussed in GB 2 007 734 which proposes to use a combination of a fatty quaternary ammonium salt having two long chain alkyl groups together with an oily substance.
Concentrated fabric softeners have been described for instance in EP 56 695, EP 13 780, DE 26 31 114 and EP 60 003, and a process for the preparation of concentrated fabric softening compositions is disclosed in EP-A-316 996.